Electric lamp or similar device and method of manufacture



M. L. STONE April 27, 1954 ELECTRIC LAMP OR SIMILAR DEVICE AND METHOD OF MANUFACTURE Filed Oct. 31, 1951 EMmJW Inventor- Melvin L. Stone His Attorney Patented Apr. 27, 1954 UNITED STATES PATENT OFFICE ELECTRIC LAMP OR SIMILAR DEVICE AND METHOD OF MANUFACTURE Application October 31, 1951, Serial No. 254,076

Claims.

My invention relates in general to electric lamps and to a method of manufacture thereof, and more particularly to a mount supporting arrangement therefor.

Electric incandescent lamps of the high wattage type are generally constructed at present with a terminal or base arrangement, commonly known as a mogul bipost base, wherein the lamp mount is supported from hollow terminal posts which are fusion-sealed to and project endwise from the neck end of the lamp envelope, the mount having side current conductors extending into the hollow interior of the terminal posts and fixed therewithin so as to support the mount in place in the envelope and electrically connect the filament thereof to the terminal posts. Up to the present, it has been the general practice in the manufacture of such type lamps to employ current conductors in the form of channelshaped members of the necessary strength and rigidity to properly support the mount in place. The use of such channel-shaped conductors, however, has the disadvantage that, because of their appreciable cross-sectional width, the concentrated filaments normally employed for such type lamps would be offset to an excessive and objectionable degree from the axial plane of the lamp through the conductors if the filament were to be welded across the outer sides. of the channel flanges. As a result, lamp mounts utilizing such channel conductor members are unadaptable to welding of the filament and filamentsupporting bridges to the conductors and therefore unadaptable to high-production jig assembly. For such reasons, it is highly desirable to employ conductors in the form of ordinary round wires which enable the filament to be welded to the conductors Without objectionably ofisetting the filament from the axial plane of the lamp through the conductors. Such a mount construction not only lends itself to high-speed, precision, jig assembly thereof by Welding operations but also provides, among other things, a mount of higher shock resistance when the lamp is unl-ighted which serves to prevent breakage of the filament by shock and maintains it in its initially fixed or centered position in the lamp envelope relative to the terminal posts of the lamp.

It is an object of my invention, therefore, to provide an electric lamp of the type provided with hollow terminal posts and having side conductors of rigid wire firmly fixed within and connected to the interior of the hollow terminal posts.

Another object of my invention is to provide an effective fastening arrangement for fixedly connecting a rigid wire lead-in conductor of an electric lamp to the interior of a tubular terminal post of the lamp.

Still another object of my invention is to pro vide an improved method of inserting and fixedly fastening a rigid wire lead-in conductor of an electric lamp into the interior of a hollow terminal post.

A further object of my invention is to provide a novel form of fastening clip for securing a wire to the interior of a tubular member.

In accordance with one aspect of the invention, an electric lamp mount having rigid Wiretype side conductors is supported in place from hollow terminal posts sealed to the lamp envelope by preferably forming the conductor wires with bent terminal ends and hooking the said ends over the rims" of split-sleeve clips with the conductor wires extending along the outer sides of the split sleeves, and then contracting and pushing the spring clips into the hollow interior of the posts to thereby push against the bent conductor ends hooked over the clips and thus pull the conductor wires along with the spring clips into the posts and expansibly clamp the said wires firmly in place therein against the inner walls of the posts. According to a further aspect of the invention, the split sleeves preferably are each formed with a longitudinal groove in their outer side within which the conductor wire is received and which is preferably located at a point approximately diametrically opposite the split in the sleeve. The said groove preferably terminates in a notch in the rim of the sleeve within which the bent end of the conductor wire is hooked to lock it in place on the clip.

Further objects and advantages of my invention will appear from the following detailed description of a species thereof and from the accompanying drawing.

In the drawing, Fig. l is an elevation of an electric incandescent lamp comprising my invention; Fig. 2 is an exploded perspective view of the terminal construction of the lamp shown in Fig. 1; Fig. 3 is a fragmentary longitudinal section through one of the terminal posts of the lamp; Fig. 4 is a transverse section through the terminal post on the line 44 of Fig. 1; and Fig. 5 is a sectional view similar to Fig. 4 of a modification of the invention.

Referring to the drawing, the invention is there shown as applied to an electric incandescent lamp of the high wattage type and comprises a sealed glass envelope or bulb I having a neck portion 2 and provided with a terminal structure of the mogul bipost type comprising a pair of hollow tubular metal posts 3, 3 fusion-sealed to a glass cup or header portion 2 of the bulb neck 2 and projecting endwise therefrom in substantially parallel side-by-side relation. The envelope I may be made of a hard borosilicate glass and the terminal posts 3 may be formed of copper. The posts 3 are comprised of a cylindrical outer portion 4 and an enlarged diameter inner or skirt portion 5 which is tapered to a feather edge and is embedded and sealed in the rims of glass nipples 6 projecting endwise from the glass cup portion 2' of the envelope neck 2. The envelope I is exhausted and gas-filled through an exhaust tube 1 which communicates with the interior of the envelope and which is subsequently tippedoff, as indicated at 8, to hermetically seal the envelope.

Mounted Within the envelope I and supported therein from the terminal posts 3 is a mount structure 8 comprising a pair of relatively rigid side conductor wires I9, I8 across which is connected a filament II. In the particular case illustrated, the filament II is of the monoplane type and comprises a wire of suitable refractory metal, such as tungsten, formed with a plurality of parallel side-by-side coiled segments I2 disposed in a common plane and joined at their adjacent ends by connecting uncoiled bight portions I3 and I4. At its opposite ends the filament II is provided with laterally extending coiled end legs I5 which are welded to the side conductor wires -Il so as to position the filament between and substantially in the plane of the two side conductor wires III, II! and in accurate relation to the socket engaging reference portions of the terminal posts 3. The filament segments I2 are supported in place, and the two conductor wires II], I0 rigidly tied together, by means of upper and lower insulating bridge members I6 and II, respectively, which are fastened across the lead-in conductor wires Ill and are provided with anchor wires I8 which are hooked onto the bights I3, I4 of the filament.

As shown in Figs. 3 and 4, the side conductor wires or rods II] are clamped to the interior wall of the hollow posts 3 by spring clips 20 in the form of contractible split sleeves having, in their normal uncontracted condition, an outside diameter slightly greater than the inside diameter of the cylindrical outer end portions 4 of the terminal posts 3. The split sleeves 28 are made of a suitable spring material such as Phosphor bronze, or steel of springy character. For the purpose of effecting the insertion and clamping of the conductor wires ID in the terminal posts 3, the ends of the said conductor wires which are to be fastened to the terminal posts are preferably formed, in accordance with the invention, with bent end portions 2I which may be in the shape of hooks and which are hooked over and engage the rim of the spring sleeves 2i! and are received therewithin. as shown in Fig. 3. To fasten the conductor wires =19 to the posts 3 the spring clips 20, together wit-h the conductor wires hooked over their rims and extending along their outer sides as shown in Fig. 2, are contracted and pushed into the hollow interior of the cylindrical outer portions 4 of the posts 3 preferably to the very ends of the latter, as shown in Fig. 3. The expansive force of the spring clips 20 then clamps the conductor wires ID firmly in place against the inner wall of the terminal post portions 4 and at the same time provides a good electrical connection therebetween. To facilitate insertion of the split sleeve clip 2; into the terminal post portion 4, the forward end of the sleeve, i. e., the end to be inserted first into the terminal post, is slightly tapered or rounded inwardly, as indicated at 22.

In order to accommodate the lead-in conductor wire I9 between the outer side of the sleeve 20 and the inner wall of the tubular post portion 4, the sleeve 20 is formed with a longitudinal indentation 23 extending the full length of the sleeve and alongside which the conductor wire extends. The depth of the said indentation 23 is such that the conductor wire I0 lies partly outside the outer circumference of the sleeve 20 so as to assure that the wire will be effectively clamped between the outer side of the sleeve 20 and the inner side of the post portion 4. As shown, the indented wall portion 23 of the sleeve 29 is preferably in the form of a longitudinal groove which is located approximately diametrically opposite the split 24 in the sleeve and is of generally semi-circular cross section (Fig. 4) corresponding in size to but of slightly smaller depth than the diameter of the conductor wire I0 so as to more or less snugly receive the con ductor wire and thus longitudinally position it in place paralled to the sleeve axis. Also, the said sleeve 26 is formed with a notch 25 in its rim at the forward end thereof, i. e., the nosed-in end 22 which is inserted first into the terminal post 3, the said notch 25 being in longitudinal alignment with the groove 23 and being of a width to snugly receive the bent or hook end 2| of the conductor wire N.

Fig. 5 illustrates a modified form or spring clip 26 according to the invention wherein the longitudinaily extending conductor-receiving indentation or groove 2'? in the contractible split sleeve 26 is formed by turning or bending inwardly a small portion of the sleeve wall, at either side of the split 28 therein, to form inturned flanges 29, 29 extending throughout the full length of the split sleeve. In theassembled position of the modified split sleeve clip 26 and conductor wire l0 within the terminal post portion 4, the inturned fianges 29 of the spring clip firmly clamp the conductor wire against the inner wall of the terminal post portion 4, as shown.

In the fabrication of a lamp according to the invention, the two conductor wires III are hooked over respective spring clips 20 or 26 and the said spring clips then pushed into the terminal post portions 4 to thereby clamp the conductor wires in place within the terminal posts 3 which extend from the glass cup or flare portion 2' of the lamp mount 9. The filament I I and its support bridges I5, I'|' are then welded in place on the conductor wires I0, preferably by means of suitable jig arrangements similar to that shown and described in my U. S. Patent 2,473,919, which insure the accurate positioning and support of the filament relative to the socket-engaging reference portions of the terminal posts 3. The completed mount 9 is then sealed into the envelope I by fusion-sealing the rim of the glass cup or fiare portion 2 of the mount 9 to the rim of the envelope neck 2, as indicated at 30. Thereafter, the envelope I is exhausted and gas-filled through the exhaust tube 1 which is then tippedoff in the conventional manner, as indicated at 8, to hermetically seal the envelope and complete the lamp.

Although a preferred embodiment of my in vention has been disclosed, it will be understood that the invention is not to be limited to the specific construction and arrangement of parts shown but that they may be widely modified within the spirit and scope of my invention as defined by the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric lamp comprising an envelope, a hollow terminal post sealed to said envelope with its hollow interior in communication with the interior of said envelope, a rigid solid-type conductor wire within said envelope and extending into the hollow interior of said post, a splitsleeve spring clip contractibly fitted into said post and clamping the said conductor wire firmly and laterally immovable in place therein against the inner wall of said post, said conductor wire having a bent end within the post hooked over the rim or" the sleeve innermost or" said post.

2. An electric lamp comprising an envelope, a hollow terminal post sealed to said envelope with its hollow interior in communication with the interior of said envelope, a rigid conductor Wire within said envelope and extending into the hollow interior of said post, and a split-sleeve spring clip contractibly fitted into said post and clamping the said conductor wire firmly and laterally immovable in place therein against the inner wall of said post, said sleeve having a notch in the rim thereof innermost of said post, and said conductor wire being formed with a bent end hooked over the rim of said sleeve within the said notch thereof.

3. An electric lamp comprising an envelope, a hollow terminal post sealed to said envelope with its hollow interior in communication with the interior of said envelope, a rigid conductor Wire within said envelope and extending into the hollow interior of said post, and a split-sleeve spring clip contractibly fitted into said post and clamping the said conductor wire firmly and laterally immovable in place therein against the inner wall of said post, said sleeve having a longitudinal groove in its outer side terminating in a notch in the rim of the sleeve at that end thereof innermost of said post, and said conductor wire extending through and being received within said groove and having a bent end hooked over the said rim of the sleeve within the said notch thereof.

4. A spring clip for fastening a wire to the interior of a tubular member comprising a springoontractible split sleeve having a longitudinally extending wire-receiving groove in its outer surface terminating at one end in a notch in the rim of the sleeve for receiving a bent end of the Wire.

5. A spring clip for fastening a wire to the interior of a tubular member comprising a springcontractible split sleeve having a normal outside diameter slightly greater than the inside diameter of said tubular member and having a longitudinally extending wire-receiving groovein its outer surface extending the full length thereof and terminating at one end in a notch in the rim of the sleeve, said notch being of a width to snugly receive a bent end of the wire.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,275,961 Maynard Aug. 13, 1918 1,696,568 Fogel Dec. 25, 1928 2,439,886 Denmark et a1. Apr. 20, 1948 

